Casio SF-8500, Service Manual & Parts List

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10-4. Gate array pin descriptions (
µ
PD65005GC-566-3B6)
Pin No. Name In/Out Status Status Description
of OFF of ON
32, 22 GND1, 2 In L L GND terminal
1, 19 VDD1, 2 In H H Main battery positive terminal (+5V)
2 Vo1 Out H H VDD output terminal (4.5V)
31 PDB In L H Power on switch signal from gate array
10-5. Power supply chip IC pin descriptions (SC371015FU)
Pin No. Name In/Out Status Status Description
of OFF of ON
1~6, 8, 9 OI7~OI0 In/Out L L Not used
7, 33 GND In L L GND terminal
10 B15 In L Pulse Address input
11~13 A15,A01,A00 In L Pulse Address input
14 N.C. - - - Not used
15 DT In H Pulse GC signal input
16~23 IO0~IO7 In/Out L Pulse Data bus line
24 CSB In H Pulse Chip select signal from CPU
25 MON Out L L Not used
26 LSI In L L Connected to GND
27 LSO Out H H Always "H"
28 PDN In H H Power down detection input
29 BLI In H H Battery detection V comp1 input
30 DEB Out H Pulse Chip selection signal for ROM (Charactor generator)
31 VIN In L H Power on signal input
32 VOT Out L H Power on signal output
34 VDD In H H VDD terminal
35 OEI In H Pulse Read signal input
36 WEI In H Pulse Write signal input
37 BBC Out L Pulse Memory back-up battery scanning signal
38 CDE In L H IC card detection signal input
39 VOB Out H L ROM power switching signal (Operation program)
40 SWO Out L L Main switch control signal
41 BCN In H H BCON signal from CPU
42 MDP In H L MDP2 signal from CPU
43 OEO Out L Pulse Read signal for ROM
44 WEO Out L Pulse Not used
45, 51 A19, A16 In L Pulse Address input
46, 47 R15, R16 Out L Pulse Address output
48 EOB In H Pulse Chip enable signal from CPU
49 RS0 Out H Pulse Chip enable signal for ROM (
µ
PD27C4001EBGW-304)
50 CS3 In H Pulse Chip select signal from CPU
52 RS3 Out H Pulse Chip enable signal for ROM (Character generator)